Retz. 



864 



page 302, plate 25, figs. 13-17, dorsal valves, at various ages ; 

 18, profile of 14; 19, ventral valve showing mesial groove ; 20, 

 front view of 14 ; 21, ventral, small, long, mature ? valve with 

 finer plications. Niagara limestone. Vh. 



Retzia granulifera. See Trematospira granulifera. Illh. 



Retzia mormonii. {TerehTatula mormonii^ Marcou, Geol. 

 N. America, 1858, p 51. Retzia punctilifera, Shumard, Trans. 

 St. Louis Acad. Sci. 1858, Vol. 1, p. 220.) Collett's Indiana Rt. 

 1883, page 136, plate 35, figs. 10, 11, 12, enlarged one quarter, 

 belly, back and side views. Widely distributed and easily 

 identified in the Coal Measures. X///.— Note. The iigiire 

 will he given in the Appendix. 



Retzia multistriata, Billings. Geology of Canada, 1863. 

 458 page 958, fig. 458, surface of the dorsal 

 valve. Lower Helderberg forrrthtion, VI- 



Retzia punctulif era. See R. mormonii. XIII. 

 Retzia verneuilliana. See Eumetria vern. XL 

 Rhabdoearpon acuminatum, Newberry. Pal. Ohio, Vol. 1, 



6. MILd>. 8. 



